Abstract
Enzymatic browning is a major problem in the quality loss of fruits and vegetables. It is also deleterious flavor, nutritional values and consumer’s acceptance. Sulfites are widespread agents used to control browning reaction. Due to adverse health effects, they could be a problem for human health. Thus, non-sulfite antibrowning agents are searched for food industry. Rice bran is a by-product from rice milling industry. It is a good source of natural antioxidants and phenolic acids. Therefore, the objective of this research was to investigate the effect of rice bran extract prepared by spray-drying on enzymatic browning inhibition in potato puree. Rice bran extract (RBE) was prepared by distilled water (DW) extraction. It was spray-dried to obtain spray-dried RBE powder (SD-RBE). The solution of SD-RBE powder was investigated for its enzymatic browning inhibition in potato puree by color measurement at room temperature for 6 hr. The browning values were calculated. Potato PPO inhibition was studied by measuring absorbance at 420 nm with catechol as substrate. SD-RBE solution showed greater enzymatic browning inhibitory efficiency than DW. Browning values and a* values of potato puree treated with SD-RBE solution were lower; whereas, L* and b* values were higher than those treated with DW during storage for 6 hr (p≤0.05). Its browning, a*, L* and b* values at 6 hr storage were 25.35, 4.05, 54.12 and 18.93, respectively; while those of DW treatment were 38.12, 5.47, 45.55 and 12.41, respectively. SD-RBE showed high potato PPO activity inhibition with the value of 66.12%. The results revealed that SD-RBE exhibited enzymatic browning inhibition in potato puree. Thus, SD-RBE has a potential to be used as a natural antibrowning agent for potato puree.
